Hello, I am running an LCA with four indicators, and I am coming upon the following error message, particularly when I specify more classes:
ONE OR MORE PARAMETERS WERE FIXED TO AVOID SINGULARITY OF THE INFORMATION MATRIX. THE SINGULARITY IS MOST LIKELY BECAUSE THE MODEL IS NOT IDENTIFIED, OR BECAUSE OF EMPTY CELLS IN THE JOINT DISTRIBUTION OF THE CATEGORICAL VARIABLES IN THE MODEL.THE FOLLOWING PARAMETERS WERE FIXED: 9 24 26 32 33 34 35 11
THE MODEL ESTIMATION TERMINATED NORMALLY
THE DEGREES OF FREEDOM FOR THIS MODEL ARE NEGATIVE. THE MODEL IS NOT IDENTIFIED OR TOO MANY CELLS WERE DELETED. A CHI-SQUARE TEST IS NOT AVAILABLE.
What exactly is happening, and do I need to be worried about it? It looks like because of this, the Pearson chi-square is not calculating.
Also, when I go to the "Plot" tab, the "View Plots" option is grayed out. Any idea why this might be?